mercaptoethanol
/məːkaptəʊˈɛθənɒl/Chemistry
noun
A liquid, HOCH2CH2SH, used as an intermediate in organic synthesis, as a chain transfer agent in polymerization reactions, and in buffer solutions to maintain protein sulphydryl groups in a reduced state; 2-hydroxyethylmercaptan.
Origin
1940s; earliest use found in Biochemical Journal. From mercapto- + ethanol.